Generally, a tungsten-halogen quartz lamp is mainly composed of a lamp housing, a glass supporting bar, a filament, molybdenum foils and terminals. In some kinds of tungsten-halogen quartz lamps, the glass supporting bar is horizontally disposed in an upper portion of the lamp housing, and the filament is stretched between the glass supporting bar at an upper portion of the lamp housing and two molybdenum foils at a lower portion of the lamp housing. For the tungsten-halogen quartz lamp with such a structure, in order to elongate a service life of the tungsten-halogen quartz lamp, it is crucial to prevent the glass supporting bar from falling down and ensure a secure fixation of the glass supporting bar on the upper portion of the lamp housing. A conventional manner for fixing the glass supporting bar to the upper portion of the lamp housing is to form two small concaves on the lamp housing at the positions slightly below both ends of the glass supporting bar respectively. In a normal condition, the two small concaves may support the glass supporting bar and fix the same on the lamp housing. However, when the tungsten-halogen quartz lamp suffers continuous jolts, vibrations or impacts during a transportation or storage period, or during a working period, the glass supporting bar may be displaced away and falls down from the small concaves. As a result, the filament may form a short circuit and the lamp may be damaged.